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And just for information sake, those long feed lines (parallel feed lines) up a mountain to an antenna used to be called a 'passive repeater'. Same for those cell antennas glued to a window of a car with a smaller antenna connected to the inside of the window. They've been around for an extremely long time. In a few cases they can actually improve reception, but not in most. That deals primarily in the losses in the feed lines.
Depending on the number of those splices and how they are done, they can negate the use of very low loss 'hardline'. Not as much on HF as on VHF/UHF, but there's still a loss at HF with improper 'splicing'.
For very long feed line runs, the 'ohmic' losses can and do amount to enough that an antenna (load) doesn't even have to be connected to that other end and the SWR will look very nice. That distributed 'ohmic' loss fools an SWR meter into thinking there's a nicely matched load on the end of that cable when there actually isn't anything there.
None of all that even touches on the impedance mismatch possible with dissimilar impedance cables, or the losses associated with that mismatch.
- 'Doc

<blockquote data-quote="W5LZ" data-source="post: 357153" data-attributes="member: 129">And just for information sake, those long feed lines (parallel feed lines) up a mountain to an antenna used to be called a &#039;passive repeater&#039;.&nbsp; Same for those cell antennas glued to a window of a car with a smaller antenna connected to the inside of the window.&nbsp; They&#039;ve been around for an extremely long time.&nbsp; In a few cases they can actually improve reception, but not in most.&nbsp; That deals primarily in the losses in the feed lines.Depending on the number of those splices and how they are done, they can negate the use of very low loss &#039;hardline&#039;.&nbsp; Not as much on HF as on VHF/UHF, but there&#039;s still a loss at HF with improper &#039;splicing&#039;.For very long feed line runs, the &#039;ohmic&#039; losses can and do amount to enough that an antenna (load) doesn&#039;t even have to be connected to that other end and the SWR will look very nice.&nbsp; That distributed &#039;ohmic&#039; loss fools an SWR meter into thinking there&#039;s a nicely matched load on the end of that cable when there actually isn&#039;t anything there.None of all that even touches on the impedance mismatch possible with dissimilar impedance cables, or the losses associated with that mismatch.&nbsp;- &#039;Doc</blockquote>

[QUOTE="W5LZ, post: 357153, member: 129"] And just for information sake, those long feed lines (parallel feed lines) up a mountain to an antenna used to be called a 'passive repeater'. Same for those cell antennas glued to a window of a car with a smaller antenna connected to the inside of the window. They've been around for an extremely long time. In a few cases they can actually improve reception, but not in most. That deals primarily in the losses in the feed lines. Depending on the number of those splices and how they are done, they can negate the use of very low loss 'hardline'. Not as much on HF as on VHF/UHF, but there's still a loss at HF with improper 'splicing'. For very long feed line runs, the 'ohmic' losses can and do amount to enough that an antenna (load) doesn't even have to be connected to that other end and the SWR will look very nice. That distributed 'ohmic' loss fools an SWR meter into thinking there's a nicely matched load on the end of that cable when there actually isn't anything there. None of all that even touches on the impedance mismatch possible with dissimilar impedance cables, or the losses associated with that mismatch. - 'Doc [/QUOTE]

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